// Open connects to the server described by the given
// info, waits for it to be initialized, and returns a new State
// representing the environment connected to.
//
// A policy may be provided, which will be used to validate and
// modify behaviour of certain operations in state. A nil policy
// may be provided.
//
// Open returns unauthorizedError if access is unauthorized.
func Open(info *Info, opts mongo.DialOpts, policy Policy) (*State, error) {
logger.Infof("opening state, mongo addresses: %q; entity %q", info.Addrs, info.Tag)
di, err := mongo.DialInfo(info.Info, opts)
if err != nil {
return nil, err
}
logger.Debugf("dialing mongo")
session, err := mgo.DialWithInfo(di)
if err != nil {
return nil, err
}
logger.Debugf("connection established")
_, err = replicaset.CurrentConfig(session)
safe := &mgo.Safe{J: true}
if err == nil {
// set mongo to write-majority (writes only returned after replicated
// to a majority of replica-set members)
safe.WMode = "majority"
}
session.SetSafe(safe)
st, err := newState(session, info, policy)
if err != nil {
session.Close()
return nil, err
}
session.SetSocketTimeout(mongo.SocketTimeout)
return st, nil
}
// attemptInitiateMongoServer attempts to initiate the replica set.
func attemptInitiateMongoServer(dialInfo *mgo.DialInfo, memberHostPort string) error {
session, err := mgo.DialWithInfo(dialInfo)
if err != nil {
return fmt.Errorf("can't dial mongo to initiate replicaset: %v", err)
}
defer session.Close()
session.SetSocketTimeout(mongo.SocketTimeout)
var cfg *replicaset.Config
cfg, err = replicaset.CurrentConfig(session)
if err == nil && len(cfg.Members) > 0 {
logger.Infof("replica set configuration already found: %#v", cfg)
return nil
}
if err != nil && err != mgo.ErrNotFound {
return fmt.Errorf("cannot get replica set configuration: %v", err)
}
return replicaset.Initiate(
session,
memberHostPort,
mongo.ReplicaSetName,
map[string]string{
jujuMachineTag: agent.BootstrapMachineId,
},
)
}
// MaybeInitiateMongoServer checks for an existing mongo configuration.
// If no existing configuration is found one is created using Initiate.
func MaybeInitiateMongoServer(p InitiateMongoParams) error {
logger.Debugf("Initiating mongo replicaset; dialInfo %#v; memberHostport %q; user %q; password %q", p.DialInfo, p.MemberHostPort, p.User, p.Password)
defer logger.Infof("finished MaybeInitiateMongoServer")
if len(p.DialInfo.Addrs) > 1 {
logger.Infof("more than one member; replica set must be already initiated")
return nil
}
p.DialInfo.Direct = true
// TODO(rog) remove this code when we no longer need to upgrade
// from pre-HA-capable environments.
if p.User != "" {
p.DialInfo.Username = p.User
p.DialInfo.Password = p.Password
}
session, err := mgo.DialWithInfo(p.DialInfo)
if err != nil {
return fmt.Errorf("can't dial mongo to initiate replicaset: %v", err)
}
defer session.Close()
// Initiate may fail while mongo is initialising, so we retry until
// we succssfully populate the replicaset config.
for attempt := initiateAttemptStrategy.Start(); attempt.Next(); {
var cfg *replicaset.Config
cfg, err = replicaset.CurrentConfig(session)
if err == nil && len(cfg.Members) > 0 {
logger.Infof("replica set configuration already found: %#v", cfg)
return nil
}
if err != nil && err != mgo.ErrNotFound {
return fmt.Errorf("cannot get replica set configuration: %v", err)
}
err = replicaset.Initiate(
session,
p.MemberHostPort,
mongo.ReplicaSetName,
map[string]string{
jujuMachineTag: agent.BootstrapMachineId,
},
)
if err == nil {
logger.Infof("replica set initiated")
return nil
}
if attempt.HasNext() {
logger.Debugf("replica set initiation failed, will retry: %v", err)
}
// Release sockets, which may have been closed by mgo.
session.Refresh()
}
return fmt.Errorf("cannot initiate replica set: %v", err)
}
func init() {
stateWorkerDialOpts = mongo.DefaultDialOpts()
stateWorkerDialOpts.PostDial = func(session *mgo.Session) error {
safe := mgo.Safe{
// Wait for group commit if journaling is enabled,
// which is always true in production.
J: true,
}
_, err := replicaset.CurrentConfig(session)
if err == nil {
// set mongo to write-majority (writes only returned after
// replicated to a majority of replica-set members).
safe.WMode = "majority"
}
session.SetSafe(&safe)
return nil
}
}
